The performance of horizontal axis tidal current turbines (HATCT) strongly depends on their geometry. According to this fact, the optimum performance will be achieved by optimized geometry. In this research study, the multi objective optimization of the HATCT is carried out by using four different multi objective optimization algorithms and their performance is evaluated in combination with bla...

An artificial neural network based model can effectively predict any functional relationship. In this paper, a neural network model is used to predict power coefficient and torque coefficient of a two bladed airfoil shaped H-rotor as function of different input parameters. The important input parameters considered are blade tip speed, free stream velocity with blockage and rotor inlet velocity....

introduction: some clinicians use a handheld screw driver instead of a torque wrench to definitively tighten abutment screws. the aim of this study was to compare the removal torque of one-piece and two-piece abutments tightened with a handheld driver and a torque control ratchet. methods: 40 iti implants were placed in acrylic blocks and divided into 4 groups. in groups one and two, 10 iti one...

We motivate and analyse a reaction-advection-diffusion model for the dynamics of a phytoplankton species. The reproductive rate of the phytoplankton is determined by the local light intensity. The light intensity decreases with depth due to absorption by water and phytoplankton. Phytoplankton is transported by turbulent diffusion in a water column of given depth. Furthermore, it might be sinkin...

Analysis of droplet formation in microfluidic systems is important to understand the operation of these devices, and to permit optimal design and process control. Droplet formation in microfluidic Tjunction devices was studied using experimental and numerical methods. The simulations agree well with experimental data from PDMS devices; they show that droplet pinch-off is controlled not by visco...

Model predictive controls (MPCs) with the merits of non-linear multi-variable control can achieve better performance than other commonly used methods for permanent magnet synchronous motor (PMSM) drives. However, conventional MPCs have various issues, including unsatisfactory steady-state performance, variable switching frequency, and difficult selection appropriate weighting factors. This pape...

We analyze the global transport properties of turbulent Taylor-Couette flow in the strongly turbulent regime for independently rotating outer and inner cylinders, reaching Reynolds numbers of the inner and outer cylinders of Re(i) = 2×10(6) and Re(o) = ±1.4×10(6), respectively. For all Re(i), Re(o), the dimensionless torque G scales as a function of the Taylor number Ta (which is proportional t...

In previous work (physics/0004026) was shown, with the help of numerical calculations, that the effective Brown temperature for charged particle is lower than that for particle without charge. Here we derive this result without numerical calculations, integrating the delay equation analytically, as for zero, so for nonzero viscosity. To describe motion of charged Brown particle in so called " e...